Full-color Vision Restoring Stem Cells Identified For First time

Stem cells could be used selectively to restore different functions of vision as needed, implies new research findings by University of Alberta scientists. The two most important photoreceptors are rods and cones, which in humans enable night vision, and full-color daytime vision, respectively. While there has been some success in restoring rods, usually in rodents, the researchers now observed that a zebrafish's stem cells can selectively regenerate only the cones in its retina.

"This is the first time in an animal research model that stem cells have only repaired damaged cones," said UA lead researcher Ted Allison. "For people with damaged eyesight repairing the cone retinal cells are most important because they would restore day-time color vision."

Allison says that for some time geneticists have known that stem cells in zebrafish can replace damaged vision cells, but not whether those cells could be instructed to only replace the cones. That is a significant difference to previous experiments, which were conducted on nocturnal rodents that require good night vision, and managed to restore some of the prevalent rods, but not cones.

The findings shows some hope for stem cell therapy that could regenerate damaged cones in people, especially in the cone-rich regions of the retina, the researchers say. Allison says the next step for his team is to identify the particular gene in zebrafish gene that activates repair of damaged cones.